Re: New Emacs facilities from Gnus

[Manoj Srivastava]

Hi,
On Sun, 04 Nov 2007 14:56:48 -0500, Richard Stallman <address@hidden> said: 

>     ;;; hashcash.el --- Add hashcash payments to email
>     ;; Maintainer: Paul Foley <address@hidden>

> What does this do?  What are hashcash payments?

        This is a device used for fighting Spam.  The sender creates a
 header in the outgoing mail for each recipient; this hash is
 computationally expensive to create, but easy to veryfy, asnd the
 string used as input contain the destination address and a timestamp,
 so it is not easy to reuse.

        Popular Spam prevention software like spamassassin verifies the
 hash, and if successful, scores the mail as not Spam. It also creates a
 store of hashcash numbers found to prevent replay attacks.

        So, as a sender, I have my computer spend a few seconds while
 sending out mail in return for a higher likelyhood that my email does
 not end up in the spam filter.

        The example given on the hashcash page is:
 % echo -n 0:030626:address@hidden:6470e06d773e05a8 | sha1
 00000000c70db7389f241b8f441fcf068aead3f0

        This is a hashcash created for address@hidden  on
 03/06/26, which has an 32-bit collision with the all 0 string.


> Will this work with sendmail.el and rmail.el?

        It does work with sendmail.el, as far as I can tell.

        manoj
http://www.hashcash.org/faq/

-- 
It's not that I'm afraid to die. I just don't want to be there when it
happens. Woody Allen
Manoj Srivastava <address@hidden> <http://www.golden-gryphon.com/>  
1024D/BF24424C print 4966 F272 D093 B493 410B  924B 21BA DABB BF24 424C